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%I #7 Feb 02 2020 09:02:48
%S 8,16,33,63,118,216,395,715,1281,2279,4036,7102,12441,21722,37797,
%T 65558,113422,195759,337148,579465,994194,1703072,2912869,4975222,
%U 8486672,14459492,24608418,41837580,71060409,120585504,204452804,346372172,586359050,991915208
%N a(n) is the smallest composite k such that Sum_{composites j = 4, ..., k} 1/j exceeds n/2.
%C Lim_{n->infinity} a(n+1)/a(n) = sqrt(e).
%F a(2n) = A076751(n).
%e a(1) = 1 because 1/4 + 1/6 = 0.41666... < 1/2 but 1/4 + 1/6 + 1/8 = 0.54166... > 1/2.
%Y Cf. A016088 (sum of reciprocals of primes exceeds n), A076751 (sum of reciprocals of composites exceeds n), A103592 (sum of reciprocals of primes exceeds n/2).
%Y Cf. A019774 (sqrt(e)).
%K nonn
%O 1,1
%A _Jon E. Schoenfield_, Feb 01 2020
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